This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. xc2xa7119 from an application entitled HARD DISK DRIVE APPARATUS earlier filed in the Korean Industrial Property Office on the 22nd day of September 1998, and there duly assigned Serial No. 39265, a copy of which is annexed hereto.
1. Technical Field
The present invention relates to a magnetic disk drive, and more particularly, to a latch system for a head of a hard disk drive.
2. Related Art
A hard disk drive (HDD) which is widely used as an auxiliary storage device of a computer has a circuit assembly for mounting major circuit parts on a printed circuit board assembly (PCBA) and a mechanical assembly called a head disk assembly (HDA) for mounting minor circuit parts and major mechanical parts including a head and a hard disk on a printed circuit board (PCB).
If a power supplied to the hard disk drive is turned OFF, a spindle motor stops rotating and a head loses its flying force. Then the head is automatically parked at a parking zone situated at the inner side of a magnetic disk under the control of a system. If vibration or shock is applied from the exterior under the state that the head is parked at the parking zone, the head may invade a data zone of the disk while it is in contact with the disk. Then a hard defect occurs on the disk and data written in the disk may be damaged. To prevent this phenomenon, most hard disk drives use a latch system.
I have found that an effectiveness of latch systems can be improved. Efforts have been made to improve devices and methods concerning latch systems and positioning systems of head units of disk drives.
Exemplars of recent efforts in the art include U.S. Pat. No. 5,187,627 for MAGNETIC LATCH AND CRASH STOP issued to Hickox et al.; U.S. Pat. No. 5,768,057 for AIR VANE LATCH INCORPORATING TOP COVER PROFILING issued to Fernandes et al.; U.S. Pat. No. 4,686,595 for APPARATUS FOR REPOSITIONING A TRANSDUCER IN THE ABSENCE OF ELECTRICAL CURRENT TO A DRIVE SYSTEM issued to Bryer; U.S. Pat. No. 5,805,384 for ACTUATOR LATCH ACTIVATED BY HEAD BRAM LOAD FOR HARD DISCDRIVES issued to Bronshvatch et al.; U.S. Pat. No. 4,786,995 for AUTOMATIC HEAD RETRACT SYSTEM issued to Stupeck et al.; and U.S. Pat. No. 5,208,713 for BISTABLE MAGNETIC/ELECTROMAGNETIC LATCH FOR DISK FILE ACTUATOR issued to Lindsay et al.
While these recent efforts provide advantages, I note that they fail to adequately provide an improved latch system of a hard disk drive apparatus.
It is therefore an object of the present invention to provide a hard disk drive using an improved magnetic latch system.
It is another object of the present invention to provide a hard disk drive using a magnet latch system without an additional magnet (inner crash stopper).
In accordance with one aspect of the present invention, a hard disk drive including a base, a hard disk which is rotatably installed in the base and has a parking zone and a data zone, an actuator which has a head situated at its leading end and a voice coil wound on a bobbin situated at its rear end and is installed in the base to shift the head onto the hard disk, and a yoke which is fixed to the base and has at least a permanent magnet, wherein the voice coil is situated between upper and lower sides of the yoke, includes a magnetic substance installed fixedly at a prescribed position of the bobbin, and situated around the boundary between magnetic poles of the permanent magnet when the head is situated at the parking zone.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a disk drive apparatus having a base, comprising: a rigid platter being rotatably installed in said base and including a data zone storing data and a parking zone; an actuator having a head reading data from or writing data to said data zone when power is supplied to said apparatus, said actuator being movably mounted to said base and transporting said head across said data zone of said rigid platter; a frame being secured to said base, said frame having an upper side and a lower side, and said frame having at least one permanent magnet forming a boundary zone between magnetic poles; a bobbin unit being installed on said actuator and having a coil wound on said bobbin unit, said coil on said bobbin unit being disposed between said upper and lower sides of said frame; and a magnetic substance being installed fixedly at a predetermined position on said bobbin unit and responding to a magnetic force of said at least one permanent magnet, said magnetic force forcing said magnetic substance toward said boundary zone between said magnetic poles when power is not supplied to said apparatus, said head being parked at said parking zone when said magnetic substance is forced toward said boundary zone, said head being moved to said parking zone in response to said magnetic force being applied from said at least one permanent magnet to said magnetic substance.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides an apparatus, comprising: a disk drive including a base; a rigid platter being rotatably installed in said base, said rigid platter including a data zone storing data and a parking zone; an actuator having a first end and a second end, said first end including a head reading data from or writing data to said data zone when power is supplied to said disk drive, said actuator being movably mounted to said base, said actuator transporting said head across said data zone of said rigid platter; a yoke having an upper side and a lower side, said yoke being secured to said base, and said yoke having at least one permanent magnet forming a boundary zone between magnetic poles; a bobbin unit having a coil wound on said bobbin unit, said bobbin unit being located at said second end of said actuator, said coil on said bobbin unit being disposed between said upper and lower sides of said yoke, said coil generating an electromotive force using a current induced by a magnetic field generated by said at least one permanent magnet; and a magnetic substance being installed fixedly at a predetermined position on said bobbin unit and responding to a magnetic force of said at least one permanent magnet, said magnetic force forcing said magnetic substance toward said boundary zone between said magnetic poles when power is not supplied to said disk drive, said head being parked at said parking zone when said magnetic substance is forced toward said boundary zone.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a disk drive apparatus having a base, comprising: a rigid platter being rotatably installed in said base and including a data zone storing data and a parking zone, said rigid platter rotating around a center axis and having an outer edge, said parking zone being disposed between the center axis and said data zone, said data zone being disposed between said parking zone and the outer edge; an actuator having a head reading data from or writing data to said data zone when power is supplied to said apparatus, said actuator being movably mounted to said base and transporting said head across said data zone of said rigid platter; a frame being secured to said base, said frame having an upper side and a lower side, and said frame having at least one permanent magnet forming a boundary zone between magnetic poles; a bobbin unit being installed on said actuator and having a coil wound on said bobbin unit, said coil on said bobbin unit being disposed between said upper and lower sides of said frame; a magnetic substance being installed fixedly at a predetermined position on said bobbin unit and responding to a magnetic force of said at least one permanent magnet, said magnetic force forcing said magnetic substance toward said boundary zone between said magnetic poles when power is not supplied to said apparatus, said head being parked at said parking zone when said magnetic substance is forced toward said boundary zone, said head being moved to said parking zone in response to said magnetic force being applied from said at least one permanent magnet to said magnetic substance; and a stopping unit being mounted to said base at a predetermined location, blocking said actuator from moving said head toward the center axis beyond said parking zone, said stopping unit not holding said actuator with a magnetic force.
The present invention is more specifically described in the following paragraphs by reference to the drawings attached only by way of example. Other advantages and features will become apparent from the following description and from the claims.